Cholesterol granulomas of the petrous apex; endonasal endoscopic approach

Objective: Cholesterol granulomas are benign lesions that sometimes occur on the petrous apex (PA). We report our experience using an endoscopic endonasal approach to remove PA cholesterol granulomas. Material and methods: A retrospective patient chart analysis was conducted at a tertiary care university hospital. Results: Four patients (3 females, 1 male) were included in this study. Patients' ages ranged from 27 to 78 years. Computed tomography (CT) and magnetic resonance imaging (MRI) for diagnosis and computer-assisted navigation were performed. The most common symptom was abducens nerve palsy. The largest granuloma measured 5 x 2 cm and was located on the left side. An endoscopic endonasal approach was chosen and navigation was applied (3/4 patients) to identify the optimal area for opening the granuloma. No complications occurred, and patients were free from recurrence during the follow-up period. Conclusion: The endoscopic endonasal approach to PA cholesterol granulomas is feasible and safe. Intra-operative navigation is recommended to identify the position of the internal carotid artery and determine the safest area for opening the granuloma without damaging the artery. Another advantage of this approach is an easier follow-up through diagnostic nasal endoscopy.